The broadcast will feature readings and addresses from people including Benedict Cumberbatch, who played the physicist in a BBC drama.

The music chosen to accompany the words is a "symbolic gesture that creates a link between our father's presence on this planet, his wish to go into space and his explorations of the universe in his mind", the professor's daughter Lucy said.

The composition will be beamed into space from the European Space Agency satellite dish at Ceberos in Spain.